Compressible elastomeric springs, including a multi-tiered stack of elastomeric pads separated by plates, have been extensively employed for absorbing energy and have gained wide acceptance for absorbing and cushioning buff and draft dynamic impact forces encountered during make-up and operation of a railway vehicle. U.S. Pat. No. 4,198,037 to Anderson and U.S. Pat. No. 5,351,844 to Carlstedt disclose related prior art methods of making compressible elastomeric springs.
Carlstedt is particularly concerned with a method of improving center-grip metal plate and its mechanical interlocking to an elastomeric pad in order to improve lateral stability of the compressible elastomeric spring.
However, further improvements are required in the method of mechanically interlocking the plate to the elastomeric pad during a cold forming process and improving axial straightness and lateral stability of the compressible elastomeric spring, particularly enabling the spring to absorb and cushion higher levels of buff and draft dynamic impact force.